Finished DIY Deck: How I Built the Deck, Stairs, and Railing

The deck is officially finished — cue the celebratory cowbells. I completed the build on a Friday and spent the next few days anxiously waiting for the county inspection. I didn’t want to celebrate until I knew everything was up to code. The inspector came yesterday afternoon and we passed. Relief washed over me as strongly as the sweat I shed building it (lesson learned: build decks in spring or fall). Here she is in her wood-clad, county-approved glory:

It’s a huge improvement from the tiny, rotting balcony we started with:

My goal was to have the deck ready before Sherry’s mom arrived from New York, so I put my head down and pushed through the final stretch. It ended up being more of a marathon than expected. We initially thought the job would take three or four weeks of intermittent work, but the combination of extreme heat, thunderstorms, inspections, equipment rentals, deliveries, summer travel (we were away more than half the weekends) and the fact I was essentially a one-man crew building a deck for the first time stretched the project to ten weeks. Still, the result makes the effort worthwhile.

I actually enjoyed the excuse to be outside, even in rough weather. Working through a Clara nap or a Saturday morning felt peaceful — a few hours of sawing and measuring with no emails or diaper changes. My dad’s help with the auger for the post holes was invaluable. A father-and-son project is a great serotonin boost.

If you’re wondering how long a deck takes: an experienced crew could finish a project like this in about a week (allowing time for local inspections). If you’re a first-timer working evenings and a few weekend days, plan for a month or two, depending on weather and inspection timing. No matter how long it takes, sinking that final screw is incredibly satisfying.

Once all the decking was down, I cut and attached the remaining posts to plan for the stairs and railing. Even though the stairs were next, setting the railing posts first helped position the stair stringers — the diagonal boards that support the treads.

You can buy pre-cut stringers, but I cut my own to match the lumber we had. Figuring rise and run felt intimidating until I used an online stair calculator to handle the math. After getting the rise (height) and run (depth) of each step, I used a framing square and a clamped straight edge to mark the cuts on a 2×12 — a trick I learned from a how-to video. Then I cut with a circular saw and finished the inner corners with a reciprocating saw so the triangular pieces would clear.

I cut and test-fit one stringer, then used it as a template to mark and cut two more. I needed three stringers for the 48-inch-wide stairway. One board had a knot that caused a small step tip to break off, so I patched it with a short piece of wood after confirming it still met code.

To attach the stringers to the deck I used angled hangers. I checked level frequently to keep the treads even. I also installed blocking between the stringers — using scrap boards to ensure consistent tread width even if the stringers weren’t perfectly level. It’s a hidden detail but important for consistency.

Next I set the posts that support the middle and bottom of the staircase into the footing holes and anchored them in wet concrete. While the concrete cured, I cut the wood for the steps — using two 2×6 boards for the tread and a 2×8 for the riser so the steps would match the deck decking and have a small overhang.

With posts set and bolted to the stringers, I screwed the treads in place — a surprisingly time-consuming task that used a lot of screws. Then I focused on the guardrail. The first parts were the 2×4 top and bottom rails that span between posts. Our county requires a maximum 4-inch gap between deck and rail, so I used a 4×4 post as a consistent spacer while installing the rails.

Attaching the railing to the stairs required careful attention to clearance and height relative to the tread noses to meet code. Cutting angles and holding pieces in place was a little mentally taxing, but it all came together. I replaced the original deck posts after realizing they were cut too short to meet the railing height over the steps — a frustrating redo, but a good lesson. This time I left the posts long and trimmed them in place once I was certain the height passed inspection.

The next day I installed the balusters — the vertical pickets — choosing a traditional layout to match the patio railing visible from the living room. That decision kept the look cohesive and the installation straightforward since the posts helped maintain spacing. The final rail cap is a 5/4 x 6 decking board; cutting the notches and angles around posts was tedious but worth the clean finish.

For the stair railing balusters I temporarily removed the cap, screwed balusters in full length, then trimmed the tops with a reciprocating saw so the cap would sit flush. I also added a handrail (required when stairs have more than three risers) and decorative post caps for a finished look.

And with that, the railing, stairs, and entire deck were complete.

I’m still a little amazed I built this myself.

Naturally, I texted my mom and a buddy to show off the finished deck.

Even though the deck is built and approved, a few tasks remain: we still need to seal it (we’ll choose the right sealer after some research) and furnish it. We’ll share a full budget breakdown after sealing. For now, you can find me sitting on the new deck, furniture-free, enjoying a cold soda and promising myself I won’t build another deck for at least ten years. Building this ranks second only to gutting and rebuilding a bathroom from the studs — that was the toughest project I’ve tackled. Anyone else wrapping up a project that took longer than planned but felt amazing to finish?

For complete deck details I documented the full process over multiple posts — from the initial vision and clearing the old balcony to selecting materials, digging post holes, setting posts, installing joists, and laying the decking boards.